Distillation of oil



H. L. DOHERTY DISTILLATION OF OIL Filed Nov. 22l 1922 Z0 Heer' /n Aug.31 1926.

Patented Aug. 31, ,1926.

UNirEo STATES 1,597,674 PATENT QFFICE.

HENB'Y L. DOHEBTY, 0F NEW YURK, N. Y., ASSUIGNOB T0 DHEBTY RESEARCH @lfPm, OF NEW YORK. N. Y., CDRPDBATIUN l' DELAWARE.

DISTILLATION OF 011i.

appunti@ and immagina, i922. semi n0. scam.

int hydrocarbons to produce lower boiling point hydrocarbons therefrom.

One of the main ditliculties encountered" in the cracking of oil is theformation of carbon. This carbon forms hard deposits on the surfaces ofthe apparatus vin which l0 the oil is being treated and the carbon deposits on the pi e stills and on the bottom of the shell stil s are verylikely to cause the stills to be burned or blistered: The formation of acarbon deposit limits the length of time that a still may be operatedwith safety, and the volume of oil, which may be treated in the stillbefore the op eration of the still must be stopped to permit the stillto be cleaned.

In a continuous cracking' processof the tvpe described in my co ndingapplication, Serial No. 361,030, ai Fsbniary 24, 1920, the oil isrepeatedly circulated from an unheated heat insulated crackin chamberthrough a directly heated pipe sti and back to the crackin chamber. Thecontinued operation of t is process has shown that when the oil has beenheated in the pipe still several times the carbon will deposit from theoil more rapidlyv than carbon will deposit from oil which has not beenprevi ously treated under cracking pressures and temperatures. It isdesirable therefore that the oil assin through the heated pipe stillshould be as ree as possible of carbon.

.The primary object of thel present Invention is to provide-a process ofand apparatus for,craclnng oil b'y. which the formation-of `carbone canbe so controlled that it will not interfere with the continued treatmentof With this object in view one feature of the invention contemplatescracking oil by repeatedly subjecting it to cracking conditions oftemperature and pressure without direct] applying heat to any oil whichcontains ree carbon.

In the preferred process of the present invention the major part of theoil cracking is carried on in compartments of a cracking chamber towhich no heat is directlyapplied. 'Ilie heat necessary for cracking theoil in the chamber is supplied by theA sensible heat and the heat ofevaporation of oil and vapors which are introduced into the crackingchamber. The direct application of the heat to the oil is 4made ina pistill, the preheated oil paing from t e still to the cracking chamber,but no oil is circulated through the pipe still which contains freecarbon.

V nother object of the invention is to provide a process of forming lowboiling point hydrocarbons from high boiling point hydrocarbons byalternately subjecting the oil to cracking and evaporation.

With this object in view, another feature of the invention contemplatescirculating oil in a closed cycle circuit, cracking the oil bydistillation under rassure and tem rature in one portion o the circuit,disti ling the oil by evaporating it under reduced pressure in anotherportion of the circuit and separately collecting condensates from the dist-illations in the dilerent portions of the circuit.

The various hi her boiling point hydrocarbonssuch as erosene, gas oiland uel oil do not all crack with equal facility under the sameconditions of pressure and temperature. Kerosene requires hi hertemperatures and ressures for cracking than oil. and a nel oil havin alower gravlty and higher boiling point t an a gas oil may beadvantageously cracked at lower temperatures and pressures than the gasoil. In the present invention the oil to be cracked is maintained in aseries of separate bodies by which the oil is cracked in stages, eachstage having a different temperature and pressure.

Accordingly, another object ofthe invention is to provide a process bywhich oil may be crackedunder di'erent conditions of temperature andpressure in order to submit the different constituents of the oil to themost favorable conditions of crackin A n accordance with this object,another in'g 'oil as a series of separate 'bodies tures and pressures ofthe bodies increasing 1n the 'direction df' flow, introducing pre-Vheated oil into the higllliest 4temperature 105 body, circulatingvapors t rough the bodies in a path countercurrent to the path of oilflow, and removing and condensm vapors leavinr the lowest temperatureborgy.

A'frrther object ofthe invention is to 110 f feature of the inventioncontemplates passprovide a process for evsrating high pressure oilresidues so thatA e desired condensates may be recovered at the maximumtemperatures and used for preheatmg oil passi to a heater or stilL WltlEthese and other objects in view, the invention consists in the improvedrocess of and apparatus for crackin oil ereinatter speeilicall describedan deued in the appended c aims.

The various features of the invention are illustrated in theaccompanying drawing, which shows atieally an a. in which the preferredprocess o vention ina be carried out.

The pre rred of the invention may be carried out with the apparatusillus the intrated in the drawing substantially as fol lows:

A boiling point hydrocarbon oil auch as cru e oil, gas oil, or fuel o'ilis supplied to a pump through a pipe 12 and creed from the pump un erpressure through a condenser 14. In passing through the con denser 14the oil is preheated b condensing vapors leaving the crachng stil Fromthe condenser 14 the oil flows through a pipe 16 and enters a condenser1S where it is further preheated by vapors from an evaporating still 20.The preheated oil from the con denser 18 flows through a pi l 2l to acondenser 22 where it is furt er heated ci vapors formed in anevaporating still The preheated oil leaving the condenser 22 flowsthrouglli a pipe 26 into a condenser 28 where it is rther heatedbyvapors formed in an eva rating still 30. The preheated oil leaving thecondenser 28 llows through a pipe 32 to a condenser 34 where it isfurther heated by vapors formed in an evaporating still 36. Thepreheated oil leaving the condenser 54 flows throih a pipe 37 to apreheatng com artment of a crac chamber 40. In e compartment 38 the o1is used to scrub cracked vapors which are formed in a crackingcompartment 42 and which pass from the compartment 42 through a valvedinlet 44 to the compartf ment 38. By scrubbing the vapors the oil isporelieated and this preheated oil leaves the ttom of the compartment 38and passes through a pipe 46 to a pump 48. The pump 48 maintains the oilunder a comparatively high pressure of from 80 to 150 pounds per :gonneinch and the size and arrangement of tubes of a pipe still 50 are eodesigned that the pump circulates the oil through the hibes atcomparatively high velocity. After the oil has been preheated andpartially ev rated by circulation through the pipe stil it flows througha pipe 152 into a separator 54. In the separator 54 the vapors areseparated from the oil and am out of the of the separator throng a pipe56 by w ch they are conducted to the lower porparatus tion of thehighest temperature com artment 58 of the craaki chamber t0. e re heatedoil collect in the se aratorM ows out of the separator thro a pipe 60 bywhich it is introduced into t e upper rt o'f the cracking chambercompartment 5 The separator 54 not only acts to separate the va rs fromthe oil, but also serves to separa e carbon and heavy terry residuesfrom the oil. The carbon and heavy terry residues settle to the bottomof the se arator and muy be intermittently drawn o through a valvedoutlet 62. The countercurrent circulation of the reheated oil andpreheated vapors throng the compartment 58 while the oil is preheated toa temperature and maintained under a hig pressure acts to thoroughlycrack higher boiling point constituents to form lower boili pointconstituents such as gasoline. In e chamber 58 there is comparativelylittle condensation and dephlegmation but the cracking operation serresto concentrate the lower boilin point hydrocarbons such as kerosene whiare not readily cracked under the tem eraturcs and pressures existing;rwithin the c amher. There is a considerable ortion of the higher boilingpoint hydrocn ns which is not broken down by the tem eratures andpressures existing in the cham ers, and this mixture of uncrackedresidue oils leaves the bottom of the compartment 58 through a pipe 64and passes to the highest temperature evaporator 36. The vapors passingthrough the compartments 58 collect in the to of the compartment and assthrough a va ved outlet 66 into a crac ingr compartment 68. The vaporsdischarged from the outlet 66 pass in under a distributing head 70, thehead being provided with a series of perforstions to distribute thevapors throughout the body of oil in the compartment 68. The oil incompartment 68 is the oil which has been previously treated at a lowertemperature in compartment 42. The temperature maintained in compartment68 is higher than the temperature maintained in compartment 42 toprovide conditions for cracking the oil which is not cracked in thelower temperature compartment. The heat for mnintainin'g the temperaturein compartment 68 is supplied by vapors which are introduced into thecompartment from the higher temperature compartment 58. To this end thetemperature of compartmentl 68 is lower than the temperature in compartfment 58 to provide a definite amount of condensation of insuiilcientlycracliecl` vapors ,in the compartment 68. The pressure in thecompartment 68 is lower than the pressure in the compartment 58 to sucha degree that the heat supplied by the latent heat of condensation ofthe insuliciently cracked vapors will crack oil in the compartment 68 orfurnish the heat of formation and the latent partment 42 is lower-densation of the collect in the lippe Atlirouirgh the compartmentsLauzon heat of evalloration of the gasoline or other low boi 'ng pointhydrocarbons to be formed in the compartment. The uncon densed lmetnpstl:nd f th ec n e up r portion o e com rtment and passphrough a valved'outla72 and are distributed by a head 74 into the oil of compartment4:2. The oil of compartment 68 then passes into the higher temperaturecompartment 58 to subjected to higher temperature and pressure stage forfurther cracki The oil in the com artment 42 is the oil which haspreviouslylbeen treated in a low temperature com artment 76. The tenirature maintain in the compartment '7 is higher than the tem raturemaintained in the compartment 6 to provide conditions for cracking oilwhich is not cracked in the low temperature compartment. 'The heat formaintaining the temperature in com artmeiit 42 is supplied by vaporsintroduce from the compartment 68. To accomplish this the temperatureincompartment 42 is lower than the temperature The pressure in thecomthan the pressure in the compartment G8 to such a de e that the heatsupplied by the latent lent of coninsulliciently cracked vapors willcrack oil in compartment 42 or furnish the hentof Vformation and thelatent heat of evaporation of gas or lower boiling point hydrocarbons tobe formed. condensed vapors assing through the compartment 42 and t e.vapors formed therein r portion of the compartment and are divided, oneportion passing through the valved outlet 44 into the preheatingcompartment 38, and the other portion of the vapors passing through avalved outlet 78 under a perforated distributing plate 80 in the lowerportion of the compartment 7'6. The oil treated in the compartment 76 isthe oil supplied from the low temperatureevaporator 20. he temperatureof the oil in the compartment 76 is lower than the temperature of theoil in the compartment 42, to permit condensation of insuliicientlycracked vapo passing rs from the com artment 42 through the body d ofthe oil. e pressure in the compartment 76 is lower than the rassure inthe compartment 42 to such a that the heat supplied by the latent heatof condensation of the insuiciently cracked vapors will crack oil in tfurnish the heat of formation and the latent heut of evaporation of thegasoline or other low boiling point hydrocarbons to be in thecompartment. The vapors passing cumulate in the tops of vapors passingthrough the compart- Ti the vapors formed therein cold The 11n-l he,compartment 76 or will t and tiow thro h outlets 82 and 84 respectivelyinto a cuogncluit 86 b which they are conducted into the oil oo o lflows through a pipe 88 into a water cooler 90 and from the cooler 90the cooled distillate Hows through a ipe 92 to a source of st e residueoil which liows out of the highest temperature cracki com artment 58contains a lar e amount of h bon constituents whic 1 are capable of)being further cracked to form lower boiling point hydrocarbons. This oilhowever has been previously subjected to high tempe und pressures orcrackin terry residues not well suited for circulation through a stillto which the heat is directly applied because the carbon and tarryresiues forni u carbon scale which seriously interferences with thecracking operation. In order to recover the portions of the crackedresidue which are suitable for cracking, this residue is evaporated, thecondens rites recovered and added to the h incoming oil to againrecirculated through the pipe still und the residue oil which is notevaporated is returned in a closed cycle circuit through the lowertemperature chamber where it can cracked to obtain any availg pointhydrocarbons therein. To accomplish this the pressure of the hightemperature oil llow'in through the pipe 64 into the evaporator 3 isreduced to a suilicient degree to permit evaporation of a definiteportion of constituents therein. These vapors pass through a ipe 94 intothe condenser'34 and are con ensed under pressure condensationcomparatively hi h boiling point constituents may be conc ensed in thecondenser 84 by means of reheatcd oil which h pnratively hightemperature.' 'Ihe vapors have a comparathus acting to imtively hightemperature; port a comparutivel)v the cooling oil of the condenser andthe pressure will serve to permit the condensation `of comparativelyhigh temperature fractions. If the pressure within the nensers34 is notas high as the pressure of oil passing through the pipe 3?, a pump 96ma)` be used to remove condensate from the condenser 34' and forcecondensate through a pipe 98 into the oil passing through the pipe 87.

The oil which is not evaported in the still 3G flows throuch a pipe 100tothe evap. orating still 30. the pressure of the oil heinq reduced bymeans of a valve 102. By this reduction of pressure n furtherevaporation of the oil will take place. these vapors passing through apipe 104 to the condenser high temperature to r vapors passin -nblc forcrackingr pu 28. The temperature of the vapors (lowing from the stillwill be lower than the from the still 36, and on the other han theoilpassing through the condenser 28 is at a lower temperature than thcoil passing through condenser 34. Condensation is carried on in thecondenser 28 under substantially the same premure as that maintained inthe still 30 and the condensate formed is removed from the condenser bymeans of a pump 106 and.I asses through a line 10S to be added to t eoil passing through the line 32. The oil which is not vaporized in thestill 30 flows through a pipe 110 to the still 24, the pressure of theoil being reduced by means of a valve 112. A further evaporation of theoil takes place in the still 24, the vapors passin through a line 114 tothe condenser where they nre condensed under substantially the samepressure as that existing in the still 24. The condensate formed in thecondenser 22 is removed by means of a pump 116 and 'forced throu h aline 118 into the oil passingthrough tie line 26. The oil which is notvaporized in the still 24 flows through a line 120 to the still 20. Thepressure of the oil assing through the line 120 is reduced tosulistantially atmos heric pressure by means of a valve 122. n the still20 the Iinal evaporation of the oil takes place, these vapors passingthrough a line 124 into the condenser 18 and the condensate formed inthe condenser is removed by a pump 126 und forced through a line 130into the oil passing through the line 21.

The unvaporized or residue oil passing through the lowest temperature varizing still 2U contains a lar amount o higher boiling point hyclrocarns which are avail- To recover this crncknble oil the residue from thestill 20 passes through a line 132 to a separator 184 *where carbon isremoved and the oil is then circulated through the cracking chamber. Thecarbon and heavy residue in the oil settle to the bottom of theseparator 134 and may be drawn oil' through a valved outlet 136. Thecleaned oil leaves the upper portion of the separator through a pipe 138and is forced under pressure into the upper por tion of the crackingcompartment 76 by means of n pump 140. The oil which is not cracked inthe compartment 76 leaves the lower portion of the compartment through apino 142 und is forced into the upper portion of thc compartment 42 bymeans of a pump 144. The pump 144 is used for controlling the pressureof the oil within the compartment 42. The oil which is not cracked inthe compartment 42leaves the bottom of the compartment through a pipe146 and is forced into the top of the compartment 68 b v means of u pump14B, the pump 148 being used for controlling the pressure within thecompgrtment 68. The oil which is not crac d in the compartment 68 leavesthe lower portion of the compartment through a pipe 150 and is forcedunder pressure into the upper portion of the compartment 58 by means ofa. pump 152. The pump 1521s used to control the preure in thecompartment 58, but the pressure in the com ait; ment 58 depends a oupon the action o the pump 48 which forces oil through the pipe stilland separator into the compartment 58.

With the construction described above it will be seen that the only oilwhich passes through the pipe still is the fresh incoming oil, and thecondenaates which nre recovered by eva rating the cracked oil. None ofthis oil t refore contains free carbon. After the oil has been passedinto the cracking circuit it remains in the circuit until it has beencompletely cracked and is only removed from the circuit in the form ofcracked vapors or as carbon and terry residues. This oil circuitconsists of,a continuous ow through a series of compartments of acracking chamber and a continuous flow through a series of evaporators.'lhe oil leaves the craclng portion of the circuit from the highesttemperature crack.- ing compartment and this high temperature oil isthen evaporated in stages to recover the lower boiling oint constituentstherefrom. The cold residue oil from the evapornting portion of thecircuit is introduced into the lowest temperature compartment of thecracking chamber and as the oil advances throu h the compartments of thecracking cham r its temperature and pressure are increased in stepsBythe multistage cracking recess out lined above1 oil may be sub'ecte toa series of dillerent conditions o pressur and temperatures to obtainthemaximum yield of gasoline or lower boiling point hydrocarbons. Theoil may be partially cracked in the lowest temperature stage and thevapors formed immediately removed from the oil bod and passed to thecondenser. TheJ uncrac ed' oil then passes to a stage having e hi hertemperature and a correspondingly igher pressu're where another portionmay be cracked. In the saine way the oil progresses through the seriesof stages and is progressively subjected to increasing temperatures toform the lower boiling pointl ydrocarbons in each stage. In the etagecracking a distinct constituept or group of constituents is acted u n 1naccordance with the' temperature an pressure existing in the st and thevapors formed pass out of the oil body into a. preceding cooler stage.As the oil advances, therefore, distinct portions of the oil are crackedand the portions of the oil which crack at the lower temperatures andpreseures` are removed before tbe oil is treated lill ln stages havingbi temperatures and pressures. Although our stages have been` shown, itis not necessary to employ four sta es, but more or less may b'e used 1naccor ance-with the character of oil. It 1s comparatively easy tomaintain the bodies of oll at the cracking temperatures, so lo as vaporsare'passing` through the oil an the temperature of t e oil is such thata portion of the vapors will. condense to supply the heat necessary forcracking t e oil 1 e. to supply the heat of formation and the latentheat of evaporation. of the vapors being formed. Bv passing the va orsthrou the oil bodies they` not onl' eat the oi but they are scrubbed ineac compartment to condense a definite ligh boiling oint orinsufficientlyl crack vapors. ese condensed vapors-may then be furthercracked to produce the lower boiling point hydrocarbons. The crackingcompartment in which these repeated and continued crackin o rations arecarried on is unheated an t ie carbon and tarry material formed may bereadil removed. Furthermoret the heat suppli to the oil in the crackingcompartments is not supplied from driving the heat through the walls ofa still and the free carbon does not bake to form a hard deposit. Thecarbon remains in such a condition that it travels with the oil towardthe collecting chambers and exaporators where it may be removed from thecircuit. This permits the cracking operation to be made substantallycontinuous and to avoid the dangerous carbon deposits or crusts.

The evaporation of the cracked oil residues in a serespf stages is veryadvantageous in that it supplies high temperature vaEors for preheatlngoil at the place where igh temperatures are necessary in order to obtaina h temperature preheating of the oil. rtbermore,by this stageevaporation comparatively high boili point constituents may be cond anrecovered. If the residue is eva orated in one stage only, a comparativy low temperature condenser would necessary in order to recover the lowboiling point vapors, and such a low temperaturecondenser is not asatisfactory means for cffecting high temperature heating of the oi] tobe cracked. Furthermore, the sta evaporation permits the latent heat of4c vapors to be recovered and the abso on of the condensates in the oilfor condensing is a means by which the sensible heat of the condensatesmay be recovered. The only heat removed from the process is the sensibleheat in the nal distillate and therefore 'a comarativel small Eipestill' may be used or supp ying the eat neoessa for crackingaargevolumcofoil. Aa owninthe drawings, the evaporation of the lresiduaoil is carried on in four stages. The number of evaporating stages maybe varied to obtain the most advantageous conditigg depending upon the cof the oil the temperature of the oil which is supplied to the pipestill. The invention therefore is not limited to a four stageevaporation but any desired number of sta s may be used to secure theadvantage ofigh temperature condensation and high tenerature heattransfer.

e preferred form of the invention having been thus described, what isclaimed as new is:

1. A process of treatin high boiling point hydrocarbons to produce owerboiling point hydrocarbons therefrom, comprising circulating oil underpressure through a heater, separating 'vapors from the heated oirlaasingthe va rs and oil through a c ing chamber w ile under pressure incounter- .current paths, passing residue oil from the cracking chamberto an evaporator and distilling it therein by reducing the oil pressure,condensing the residue vapors by a heat interchange with untreated oil,returning the residue oil from the evaporator to the cracking chamberand condensing vapors leaving the cracking chamber.

2. A process of treating high boiling point hydrocarbons to producelower boiling point hydrocarbons therefrom, comprising circulating oilunder pressure through a heater, separating vapors from the heated oil,assng the' va rs and oil through a cr g chamber u' ile under pressure incountercurrent paths, circulating oil from the cracking chamber throughan evaporator and roturning it to the cracking chamber in aclosed cycle,reducing the pressure of the oil in the eva orator to remove vaporstherefrom, and con ensing the vapors leaving the cracking chamber. Y

3. A process of treating high boiling point eased hydrocarbons toproduce lower boiling point hydrocarbons therefrom, comprisingcirculating oil under pressure through a heater, separating vapors fromtheheated oil, i .'-L ing the valxrs and oil through a c f chamber w leunder pressure in countercurrent paths, passing residue oil from thecrac chamber to an evaporator and da tilling it therein by reducing theoil p condensing the residue oil va ra b a heat interchange withuntreated oil, ad' the evaporator condensate tothe un L oil forcirculation through the beater, returning -.the residue oil from theevaporator to the cracking chamber,- and condensing the vapors leavingthe cracking chamber.

4. A process of treating high boiling point hydrocarbons to producelower boiling point hydrocarbons therefrom, comprising mrculating oilunder pressure through a heater,

lll

separating vapors from the heated oil, asscircuit crackin the oil b ituning the va rs and oil through a crac g der a and tgmperature in onechamber w ile under pressure in counterportion oft current paths,circulating oil from the cracku al oil from said crac in another poringchamber through an evaporator and retion of the circuit in stages byreducing m turning it to the cracking chamber in a the pressure of theoil in each Stage, se

cycle, reducing the pressure of tlie li'tcly condensing the vaporeformed in oil in the evaporator to remove vapors there- @ach Stege ofthe evaporation, preheating from, condensing the vapors from theevapothe 911 t0 be crlked and the evtl rator and adding them to theuntreated oil oration condenaates theieto, an inserh'ng'fc passingthrough the heater, and cond the preheated oil condensate mixture intothe vapors leaving the cra chamber. the cracking. portion of thecircuit.

5. A process of treating high oiling point 10. continuous procese ofcracking oil hydrocarbons to produce lower bo' point C9I11R1l8lng in pclosed cycle hydrocarbons therefrom, comprising circuclicliithcr the oilby distillation un so lating eil under pressure through a heater, der ahigh renureend temperature in one separating vapors from the heated oil,portion of e circuit, evaporatin the resid. ing the va re and oilthrough a caching 1&1 011 from Said by istillation chamber w 'le underpressure in counterunder a reduced pressure in porcurrent paths,circulating oil from the cracki101! 0f Athe separately collecting as ingchamber through an evaporator` and renfflldenllif Obln une turning it tothe cracking chamber in e. m thE difetn' Portions '0f circuit, 1nclosedcycle, reducing the pressure on the trodlicing oil into the'creckingportion of oil in the'evaporator to remove vapors there- #[28 Girelli?,Bild ILPPlfJ-lig heut only t0 the A from, separating carbon and heavyterry maoil being introduced into the cracking porou 'terial from theoil of the eva orator before '910D 0f the Circuit. Q l

' hamber. Y il. A of treating higher boiling 6. A continuous process ofcracking oil point liy roca-rhone to produce lower boilcomprisingcirculating oil in a closed cycle .mg point hydrocarbons therefrom,compriecircuit, cracking the oil by distillation under 111g passingresidual oil ae a series of sepa- 96 a high measure and temperature inone rlt bodice. through a chamber, the circuit, distilling the vecinalthe temperature of the bodies increasing oil from said cracking by evaretin it in the direction of dow, increasing the preeunder a reducedressure in anothgr poiion gute 0f ,the oil on the bodice ucsivply of thecircuit, an separately collectiii conn l the 011 0f 50W0f 011 mmfillmg 1donante from the distillations in the iiferhlghlyhted llld l'dltlvlyfresh ent. portions of the circuit. the heet -mpl'atllm bodyhtlmn Acontinuous process of cracking oil P011 through H18 bOdie Il i t Pacomprising circula oil in a closed cycle telll'l'nt l0 he @0W 0fv 011through the circuit, cracking the oi by distillation under bodies, and.removing and condeni .vama u high pressure and temperature in one or-POPE lelvlllg the lOweBt @I HPGIQWN yg tion of the circuit, eva rati theresi ual rl'ss of tica higher boiling oil from said cracking ydislhition of the point hy ocarhons to p nce lower oil under reducedpressure in another por. ing point hy. bons .therefrom compristion ofthe circuit, prehea oil under preel? Plmg 0l! m 811.0098810 l *n8 Ileine, and inserting it into crackin porg coniprhnents of l cracking nonof :he circuit and ce rarely ccllgcctu' F increasing the pressure of theoil n1 wh condensatee from the dietilationa in the di 0f, the Uudl mpmhtm the ferent portions of the circuit 011 t0 bo trg! 8. A .continuousprocegs of cr 0i] ducing it into the compartment having iis cle circuit,cracking' oi-l by disci stay.. formed in tbeoil the bodies of'the h ighpressure and temperature in one r. oil in the compartments in apathcountertion of the circuit, evaporating` the resi ual 0l11'rei`1t to thecirculation of the oil thereoil from said by distillation unthrough, andconde-using the vabors leav- 120 der reduced pressure in another rtionof in t theV circuit, preheatinE oil undeipopleeeure A process oftreating high boiling hyand inserting it into t e cracln' circuit,separately collecting the conhydrocarbons t mp donante from thedistillations in the dileroi usan upright column through a series 125ent `Portions of the circuit, and adding the ofcompartmenta of acracking con ensate from the evaporation to the nn succession, supglyingoil to the top of each cated. to be treated m- 9. The continuous proceseof cracking oil der pressure separa' vapors from the comprising oil in aclosed cycle heated oil and introdtulcnigg them atthe botu .usb-denaation Y 'enteinthe evaporator by aoreontheol, returning ithgudm ftren' 6.' roces o in int bonbons to Yp nce owerbo co of .mg oilto'he'treated un est toni of the oil onlumn in tem-1' artmenkanol tngthoin a flow oi ouilthrough eut redneing the pressure of the oil 1n each oithe mfartmente in auceeseon in the 'on ow of the vapors, and con EL.

pore leaving the top eoxupartment o recom of treatin Vhigh'- froearhonsto Krodue lower boiling' docu-bons t erefrom compr point h will?aaamgoil nsuocessionthro haoeneeo gm :E

ta of -a crahng ber, heatder premere and in* troducing it intothehighest temperature cnpai'tmengfnutealing thgI praure and perature 'o oin ea. compartment in ou, emla residue oil from the highest tempera comt thro an evaporator, removing hy the lower boiling pointconstituredncngthe preethe evaporator nil residue while hot to t elowest temper ture compartment of the chamber, and vapore leayin thelowest tempera- 'tune compartment of chamber Y 15. A roees of treatingh' neto produce Iihwer bo* point hy lng 'point hydrocarbons therefromcomprisingpassing oil in succession through a eeriesnf compartments of acra eham ber, heating the oil to be trea under pressun, and introducingit 'late the 4.

est tern ture com rtment, e. thresem? and tempretumpf the oil inarulatfrom the highest temperature ugh a eolica of e'raiorolm8 @wwwinea, wing timeY of the oil rn eaohrmporating ..1 hreneeesmon, sepaeonformed m each compartment heat interoli with incoming um tree oil,anti adding the condensate! to .'.poiht hydrocarbons therefrom compne-'passnoil as en up' t column suecesson't ro h a series o compex-muteber, :nain ,soeceseively her tem' aud p in eaeli of e successiveemparhnentn, su plying oil from the bottom of one eemp ment to` the topof the ment, heating' ml to sure, separating va troducmg thenLat ebottom of the high temperature eompartmeut,' introducing the heated oilat the top of the eet temperaturo compartment, passing e -vapors hetreated under through of oil therethrouh, eon

due

oon

eon- Y ntrollng Ypatheoun oompart-olthrogh therefrom an ,ini

compartments `in on to the direction oi the ow lensing vapors loew,perature oom a circulating oil resi from the hi 'teml' perature com t th an evapora or, condensing t vapo ormed inthe evaporatormnd ret the oilresidue fromthe evaporator to ature compartment of through theeountercurrent ing the lowest e Inweb(- temper the cracking cham: 1l

.'l. An oi dikt'lli'ng apparatuseomprsi a-plpe still; e vapor separatoreennecttn the still, a cracking cham a series of eompartmehts,conductors for 00 lending oil and means for leading vapors from en e oomrtment to the in said redde for new .of oi! and vapori through theeompartments, means for leading oil and meausfor leading vapori fromthe-aeparator-t'o the mt e vapors, andA e lasteom artf ment of thecracking chamber in the tion of flow o! the vapore.

.18. An oil distilling a params compria-- ingaoraelnghambervlngaeeriesof eompartmenls, eohduetors for leading eil and vapors fromone cougaar-ement go un v5 meham thoilgistilling apparatus eonilzn'ieOder iemurethroughthe i' still ehanlber, au evaporator animera! Il e forin'ewh @vom een'the iii-st eom .Y .swdwww w nected with each..eoinigartment, meanato I to the path-of dow o! th.com remue aeonnectionlhetw and the oraeing' vll ingacraeking odwith into ne g l wwwhving' eof'onnectedeol'npertments, -tur for oiifronithe enpotetoneol:.means fonoontrolling the pressure in e'aelr ,tothe cracking chembeg,)ed e Tam om w l unneion between the 'connectodyiththe 'other and thefirst compert'- 22.* An oil-distilling 'eppoi-etna comprismet, ncondenser eonnected'with eaohcoming e pipe s'tll, n oreckingjchember,meme eri4 pertinent, Ineens to 'conduct oil througlthe iunior-oi oil4frol'nthe pipe tillito the eondnsers 1in. meceason, md.- introduce, .itlumber, op evlpoi'stor, means' for into the st' means for controllingthe' leading oil fromthe cracking ohambexy .vxpor the' condenser@'mea'nej-tp is evmretoxr; meins for. conucting residlg introduce.condensate the. -oondense`rs into the oil qirciihplssxtx lto the tKipestill, chamber, xicondenser connected -wifh' the' and s eonde'meroonnwith1 e creek! cmcin'ng chambert and means inthe oonnee-V.

for .fotoni oil from the pipe still into the heayresidnee troni-the inchexber. e tion between thepipestill andb the elfackng L An' distillinipparetns eomp'schambexf and between the evnporetol: ind the ing s'pp'e' still, or chamer, ineens crackmg chamber for remou when "md uwing' therec rlhng amber, in evaporate through. withtheoreckingohember,g. oon enseil leon- In testimony whereof! eix' my igneture.

nected with the eve ntor meansto conam mem@ t epipesziu, e conauo-HENRY- L. DOHEBTY.

e evaporator back tothe crwckmg 3U,

,means for controlling the pressure in each into the pipe stili, meansfor controlling the pressure in the condensers, meansj toV com artment,a connection between the crac ing chamber and the first compartment, acondenser oonnectedwith each' compartment., means to conduct oilthrough-the condensers in succession, and introduce .it

vapor introducecondensate from the. condens'ers l into the oil circuitpassing to t-he ipe still,

and a coudenserconnected with't e cracking chamber. i

' 21. An oilf distillingapparatus 'comprising a' pipe' still, a crackingchamber, means for forcmcr oil from cracking c amber, an evaporatowiththecracking chamber, a con enser connected with the evaporator,means to cn duct condensate to' t evpipe still, a conducthe pipe stillinto the tor for leading oi'Lfromthe evaporator .back tothe crackingchamber, and a condenser connected with the cracking chamber.

22.`An oildis'tilling 4apparatus comprising a pipe Still, a crackingchamber, means `forforcin oil fromthe pipe 'stillirito thel cracking 'ciarnber, a n evaporator, means for leading oil from the cracking chambervto the eva orator; means for. conucting residue 'from 't 1e evaporatorback tol the cracking chamber, a condenser connected with the crackingchamber, and means in the connection between the pipe still andthecracking' chamber and between the evaporator and the cracking chamberfor removin carbon and' heavyV residues from-the oil flgowingtherethrough. l

In testimony whereof 1 aix my signature.

HENRY L.V DOHERTY.

' eri iiledMa'wh ai 1934, bythe se;

ughfprewiosly heated DISCLAIMER 1,597,674.-Henry L. Doherty, New York,N. Y; DISTILLATION 0F OIL. Ifatent dated August 31, 1926. Disclaimerfiled March 8, 1934, by the assignee, Doherty Research Company.

Hereby disclaims: *n

(a) From claims 6 and 10 of said Letters Patent, any recess 111 Winchoil m the closed cycle circuit is subjected to heat otherwise than tough previously heated oil which is introduced to the circuit.

(b) From claim 21, any apparatus in which thev conductor for. leading011 from the eva rator back to the cracking chamber is connected 'to thepipe still.

[Q ial Gazee March .97', 1934.]

